Online temperature compensation circuit, control method thereof and temperature compensation instrument

Abstract

The invention provides an online temperature compensation circuit and a control method thereof, and a temperature compensation instrument, the circuit comprises a sampling module, a parameter compensation module and a correction module, the sampling module is used for sampling the voltage of a port to be measured to obtain a sampling voltage, and the correction module is used for correcting the sampling voltage; the parameter compensation module generates a compensation voltage according to the reference voltage and the temperature variation before the current temperature, and the correction module corrects the sampling voltage based on the compensation voltage to obtain a target voltage, so that the target voltage is equal to the voltage of the port to be measured at the reference temperature at any temperature. According to the on-line temperature compensation circuit, temperature measurement of the circuit is achieved by adjusting the resistance value of the resistor, the temperature measurement range is wide, on-line temperature compensation of the circuit is achieved, the temperature adjustment range is wide, and precision is high.

Description

Technical Field

[0001] The present invention relates to the field of circuit design, and in particular to an online temperature compensation circuit and a control method thereof, and a temperature compensation instrument. Background Art

[0002] In the actual application of electronic circuits, when the ambient temperature changes, the performance parameters of some electronic components will change accordingly. This may lead to unstable circuit performance or even failure. Circuit temperature compensation technology is to solve the problem of performance fluctuations caused by temperature changes of electronic components, and is used to maintain the consistency of circuit performance under different temperature conditions. The circuit temperature compensation methods commonly used in the prior art have poor linearity, small compensation range, and poor compensation accuracy.

[0003] Therefore, how to provide a temperature compensation circuit with high temperature compensation accuracy, good linearity and a wide compensation range is a technical problem that urgently needs to be solved. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, the present invention provides a technical solution of an online temperature compensation circuit to solve at least one of the above-mentioned technical problems.

[0005] In order to achieve the above-mentioned purpose and other related purposes, the technical solution provided by this application is as follows.

[0006] According to a first aspect of an embodiment of the present application, there is provided an online temperature compensation circuit, comprising:

[0007] A sampling module is used to sample the voltage of the port to be measured to obtain a sampled voltage;

[0008] A parameter compensation module, used for generating a compensation voltage according to a change between a current temperature and a reference temperature;

[0009] A correction module is connected to the sampling module and the parameter compensation module, and corrects the sampling voltage according to the compensation voltage to obtain a target voltage, wherein the target voltage is equal to the voltage of the port to be measured at the reference temperature.

[0010] In one embodiment of the present invention, the sampling module includes a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a first capacitor, a second capacitor, a first operational amplifier and a second operational amplifier, the positive phase input terminal of the first operational amplifier is grounded after passing through the first resistor, the first end of the second resistor is connected to the negative phase input terminal of the first operational amplifier, the negative phase input terminal of the first operational amplifier is connected to the output terminal of the first operational amplifier after passing through the third resistor, the positive power supply terminal of the first operational amplifier is connected to the positive electrode of the first power supply, the positive electrode of the first power supply is also grounded after passing through the first capacitor, the negative power supply terminal of the first operational amplifier is connected to the negative electrode of the first power supply, the negative electrode of the first power supply is also grounded after passing through the second capacitor, the output terminal of the first operational amplifier is connected to the negative phase input terminal of the second operational amplifier after passing through the fifth resistor, the positive phase input terminal of the second operational amplifier is grounded after passing through the fourth resistor, and the negative phase input terminal of the second operational amplifier is connected to the output terminal of the second operational amplifier after passing through the sixth resistor, wherein the second end of the second resistor is connected to the voltage of the port to be measured, and the output terminal of the second operational amplifier outputs the sampled voltage to the outside.

[0011] In one embodiment of the present invention, the parameter compensation module includes a constant current source driving unit and a parameter generating unit. The constant current source driving unit generates a driving voltage based on a second power supply under the drive of a first reference voltage. The parameter generating unit is connected to the constant current source driving unit. The parameter generating unit generates a compensation voltage according to the second reference voltage and the driving voltage.

[0012] In one embodiment of the present invention, the constant current source driving unit includes a third capacitor, a fourth capacitor, a seventh resistor, an eighth resistor, a ninth resistor, an NPN transistor and a third operational amplifier, the non-phase input terminal of the third operational amplifier is grounded after passing through the third capacitor, the positive power supply terminal of the third operational amplifier is connected to the positive electrode of the first power supply, the negative power supply terminal of the third operational amplifier is connected to the negative electrode of the first power supply, the negative phase input terminal of the third operational amplifier is connected to the output terminal of the third operational amplifier after passing through the fourth capacitor, the output terminal of the third operational amplifier is also connected to the base of the NPN transistor after passing through the seventh resistor, the collector of the NPN transistor is connected to the second power supply, the emitter of the NPN transistor is grounded after passing through the eighth resistor and the ninth resistor, the negative phase input terminal of the third operational amplifier is also connected to the common end of the eighth resistor and the ninth resistor, wherein the non-phase input terminal of the third operational amplifier is connected to the first reference voltage, and the emitter of the NPN transistor outputs the driving voltage to the outside.

[0013] In one embodiment of the present invention, the parameter generating unit includes a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor, a fourth operational amplifier, a fifth operational amplifier, and a sixth operational amplifier; the second reference voltage is connected to the positive phase input terminal of the fourth operational amplifier after passing through the tenth resistor, the positive phase input terminal of the fourth operational amplifier is also grounded after passing through the eleventh resistor and the twelfth resistor, the positive power supply terminal of the fourth operational amplifier is connected to the positive electrode of the first power supply, the positive power supply terminal of the fourth operational amplifier is grounded after passing through the fifth capacitor, the negative power supply terminal of the fourth operational amplifier is connected to the negative electrode of the first power supply, the negative phase input terminal of the fourth operational amplifier is connected to the output terminal of the fourth operational amplifier, the output terminal of the fourth operational amplifier is connected to the first end of the fourteenth resistor after passing through the thirteenth resistor, and the first end of the fourteenth resistor is also connected to the first end of the fourth operational amplifier. The positive phase input terminal of the fifth operational amplifier, the second end of the fourteenth resistor is grounded, the first end of the fifteenth resistor is connected to the negative phase input terminal of the fifth operational amplifier, the negative phase input terminal of the fifth operational amplifier is connected to the output terminal of the fifth operational amplifier through the sixteenth resistor, the sixth capacitor is connected in parallel with the sixteenth resistor, the output terminal of the fifth operational amplifier is connected to the negative phase input terminal of the sixth operational amplifier through the seventeenth resistor, the positive phase input terminal of the sixth operational amplifier is grounded, the negative phase input terminal of the sixth operational amplifier is connected to the output terminal of the sixth operational amplifier through the eighteenth resistor and the nineteenth resistor, the positive power supply terminal of the sixth operational amplifier is connected to the positive electrode of the first power supply, the positive electrode of the first power supply is grounded after the seventh capacitor, the negative power supply terminal of the sixth operational amplifier is connected to the negative electrode of the first power supply, the negative electrode of the first power supply is grounded after the eighth capacitor, wherein the second end of the fifteenth resistor is connected to the driving voltage, and the output terminal of the sixth operational amplifier outputs a compensation voltage to the outside.

[0014] In one embodiment of the present invention, the correction module includes a twentieth resistor, a twenty-first resistor, a ninth capacitor, a tenth capacitor, and a multiplier, wherein the first input terminal of the multiplier is connected to the first end of the twentieth resistor, the second input terminal of the multiplier is connected to the first end of the twenty-first resistor, the third input terminal of the multiplier is grounded, the positive power supply terminal of the multiplier is connected to the positive electrode of the third power supply, the positive power supply terminal of the multiplier is further grounded after passing through the ninth capacitor, the negative power supply terminal of the multiplier is connected to the negative electrode of the third power supply, the negative power supply terminal of the multiplier is further grounded after passing through the tenth capacitor, the fourth input terminal of the multiplier is connected to the output terminal of the multiplier, and the fifth input terminal of the multiplier is grounded, wherein the second end of the twentieth resistor is connected to the third reference voltage, the twenty-first resistor is connected to the compensation voltage, and the sixth input terminal of the multiplier is connected to the sampling voltage.

[0015] According to a second aspect of an embodiment of the present application, a control method for an online temperature compensation circuit is provided, which is applied to the online temperature compensation circuit as described above, and includes:

[0016] Calibrate the compensation voltage at the reference temperature so that the target voltage is equal to the voltage of the port to be measured;

[0017] Sampling the voltage of the port to be tested at the current temperature to obtain the sampled voltage;

[0018] Performing temperature compensation on the sampled voltage according to a compensation voltage corresponding to the temperature difference to obtain the target voltage;

[0019] The temperature difference is the difference between the current temperature and the reference temperature.

[0020] In one embodiment of the present invention, the compensation voltage is calibrated at the reference temperature so that the target voltage is equal to the port voltage to be measured, including: sampling the port voltage to be measured at the reference temperature to obtain the sampled voltage at the reference temperature; adjusting the resistance value in the parameter compensation module so that the compensation voltage is equal to a preset voltage threshold, so that the target voltage is equal to the port voltage to be measured.

[0021] In one embodiment of the present invention, the sampled voltage is temperature compensated according to the compensation voltage corresponding to the temperature difference to obtain the target voltage, including: adjusting the resistance value in the parameter compensation module based on the current temperature to obtain the compensation voltage at the current temperature; and correcting the sampled voltage based on the compensation voltage at the current temperature to obtain the target voltage at the reference temperature.

[0022] According to a third aspect of the embodiments of the present application, the present application also provides a temperature compensation instrument, which includes the online temperature compensation circuit as described above, and is used to perform temperature compensation on the voltage of the port to be measured.

[0023] The present application provides an online temperature compensation circuit and a control method thereof, and a temperature compensation instrument. The circuit includes a sampling module, a parameter compensation module, and a correction module. The sampling module samples the voltage of the port to be measured to obtain a sampled voltage. The parameter compensation module generates a compensation voltage according to the reference voltage and the temperature change before the current temperature. The correction module corrects the sampled voltage based on the compensation voltage to obtain a target voltage, so that the target voltage is equal to the voltage of the port to be measured at the reference temperature at any temperature. The online temperature compensation circuit provided by the present application realizes the temperature measurement of the circuit by adjusting the resistance value of the resistor. The temperature measurement range is wide, and the online temperature compensation of the circuit is realized. The temperature adjustment range is wide and the precision is high.

[0024] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present invention, and together with the specification, are used to explain the principles of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0026] Figure 1 is a block diagram of an online temperature compensation circuit shown in an exemplary embodiment of the present invention;

[0027] Figure 2 is a specific circuit structure of a sampling module shown in an exemplary embodiment of the present invention;

[0028] Figure 3 is a specific circuit structure of a constant current source driving unit shown in an exemplary embodiment of the present invention;

[0029] Figure 4 is a specific circuit structure of a parameter generation unit shown in an exemplary embodiment of the present invention;

[0030] Figure 5 It is a specific circuit structure of the correction module shown in an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0031] The following will describe the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0032] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0033] In the following description, numerous details are discussed to provide a more thorough explanation of the embodiments of the present invention. However, it is obvious to those skilled in the art that the embodiments of the present invention can be implemented without these specific details. In other embodiments, well-known structures and devices are shown in the form of block diagrams rather than in detail to avoid making the embodiments of the present invention difficult to understand.

[0034] In electronic circuits, the resistance of most metal conductors increases with increasing temperature, which is due to the increased chance of collision between free electrons and lattice vibrations. In contrast, the resistance of some semiconductor materials may decrease with increasing temperature. In amplifiers, temperature changes can affect parameters such as the threshold voltage and current gain of transistors, which in turn affect the gain and linearity of the amplifier. This may lead to unstable circuit performance or even failure. Circuit temperature compensation technology refers to a series of measures taken to solve the problem of performance fluctuations of electronic components due to temperature changes, and is used to maintain the consistency of circuit performance under different temperature conditions. The design purpose of this circuit is to reduce the impact of changes in electronic component parameters caused by temperature changes on circuit operation. Through temperature compensation, it can be ensured that electronic equipment can operate reliably under various temperature conditions. Temperature compensation helps to reduce the failure rate caused by temperature stress, thereby extending the service life of electronic equipment.

[0035] The circuit temperature compensation methods commonly used in the prior art include:

[0036] ① Thermistor compensation uses the change in thermistor resistance with temperature for compensation. However, the temperature coefficient of thermistor is nonlinear, and it is very complicated to achieve accurate compensation over a wide temperature range. After long-term use, the characteristics of the thermistor may drift, resulting in excessive compensation deviation.

[0037] ② Bridge compensation method is used to make the reference temperature of the free end of the temperature sensor more appropriate, and to reduce the error by combining electronic components with positive temperature coefficients and negative temperature coefficients. For example, resistors with positive temperature coefficients and resistors with negative temperature coefficients are used in the circuit. When the temperature changes, the resistance values ​​of the two resistors change in the opposite direction, thereby achieving the compensation effect. However, the bridge compensation method has high noise and poor linearity.

[0038] ③DCR temperature compensation network: used to solve the problem of DCR value changing with temperature in inductor current detection. A resistive network with a negative temperature coefficient is inserted into the current detection loop to compensate for the change of DCR with temperature. This method requires the design of different compensation networks according to the specific current detection architecture to ensure that the VCX voltage (that is, the voltage across the capacitor) is only related to the inductor current and is not affected by temperature. The DCR temperature compensation network requires precise resistance values, including DCR resistors with positive temperature coefficients and compensation resistors with negative temperature coefficients. The accuracy of the resistor has a direct impact on the effect of temperature compensation. If the resistance value is inaccurate, it may result in poor compensation effect, thereby affecting the accuracy of current detection.

[0039] To solve the above problems, Figure 1 As shown, the present application provides an online temperature compensation circuit, comprising:

[0040] The sampling module is used to sample the voltage V0 of the port to be tested and obtain the sampled voltage V S ;

[0041] The parameter compensation module is used to generate a compensation voltage V according to the change between the current temperature and the reference temperature. comp ;

[0042] The correction module is connected to the sampling module and the parameter compensation module, and the compensation voltage V comp The sampling voltage V S Correction is performed to obtain the target voltage V g , where the target voltage V g Equal to the port voltage V0 under test at the reference temperature.

[0043] In detail, Figure 3As shown, the sampling module includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a first capacitor C1, a second capacitor C2, a first operational amplifier OP1 and a second operational amplifier OP2. The positive input terminal of the first operational amplifier OP1 is grounded after passing through the first resistor R1, the first end of the second resistor R2 is connected to the negative input terminal of the first operational amplifier OP1, the negative input terminal of the first operational amplifier OP1 is connected to the output terminal of the first operational amplifier OP1 after passing through the third resistor R3, the positive power supply terminal of the first operational amplifier OP1 is connected to the positive electrode of the first power supply VCC1, and the first power supply VC The positive electrode of C1 is also connected to the ground via the first capacitor C1, the negative power supply terminal of the first operational amplifier OP1 is connected to the negative electrode of the first power supply VCC1, the negative electrode of the first power supply is also connected to the ground via the second capacitor C2, the output end of the first operational amplifier OP1 is connected to the negative phase input end of the second operational amplifier OP2 via the fifth resistor R5, the positive phase input end of the second operational amplifier OP2 is connected to the ground via the fourth resistor R4, the negative phase input end of the second operational amplifier OP2 is connected to the output end of the second operational amplifier OP2 via the sixth resistor R6, wherein the second end of the second resistor R2 receives the measured port voltage V0, and the output end of the second operational amplifier OP2 outputs the sampling voltage V S .

[0044] In detail, the parameter compensation module includes a constant current source driving unit and a parameter generating unit. The constant current source driving unit generates a driving voltage V based on the second power supply VCC2 under the drive of the first reference voltage VREF1. d The parameter generation unit is connected to the constant current source driving unit, and the parameter generation unit generates a constant current source according to the second reference voltage VREF2 and the driving voltage V d Generate compensation voltage V comp .

[0045] In more detail, Figure 3As shown, the constant current source driving unit includes a third capacitor C3, a fourth capacitor C4, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, an NPN transistor Q1 and a third operational amplifier OP3, the positive phase input terminal of the third operational amplifier OP3 is grounded after passing through the third capacitor C3, the positive power supply terminal of the third operational amplifier OP3 is connected to the positive electrode of the first power supply VCC1, the negative power supply terminal of the third operational amplifier OP3 is connected to the negative electrode of the first power supply VCC1, and the negative phase input terminal of the third operational amplifier OP3 is connected to the third operational amplifier O after passing through the fourth capacitor C4. The output end of the third operational amplifier OP3 is also connected to the base of the NPN transistor Q1 through the seventh resistor R7, the collector of the NPN transistor Q1 is connected to the second power supply VCC2, the emitter of the NPN transistor Q1 is grounded through the eighth resistor R8 and the ninth resistor R9, the negative phase input end of the third operational amplifier OP3 is also connected to the common end of the eighth resistor R8 and the ninth resistor R9, wherein the positive phase input end of the third operational amplifier OP3 is connected to the first reference voltage VREF1, and the emitter of the NPN transistor Q1 outputs the driving voltage V d .

[0046] In detail, Figure 4As shown, the parameter generating unit includes a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, an eighth capacitor C8, a fourth operational amplifier OP4, a fifth operational amplifier OP5, and a sixth operational amplifier OP6; the second reference voltage VREF2 is connected to the fourth operational amplifier after passing through the tenth resistor R10. The positive phase input terminal of the fourth operational amplifier OP4 is connected to the positive electrode of the first power supply VCC1, the positive power supply terminal of the fourth operational amplifier OP4 is connected to the positive electrode of the first power supply VCC1, the positive power supply terminal of the fourth operational amplifier OP4 is connected to the ground through the fifth capacitor C5, the negative power supply terminal of the fourth operational amplifier OP4 is connected to the negative electrode of the first power supply VCC1, the negative phase input terminal of the fourth operational amplifier OP4 is connected to the output terminal of the fourth operational amplifier OP4, and the output terminal of the fourth operational amplifier OP4 is connected to the 10th via the 13th resistor R13. The first end of the fourth resistor R14 and the first end of the fourteenth resistor R14 are also connected to the positive phase input terminal of the fifth operational amplifier OP5, the second end of the fourteenth resistor R14 is grounded, the first end of the fifteenth resistor R15 is connected to the negative phase input terminal of the fifth operational amplifier OP5, the negative phase input terminal of the fifth operational amplifier OP5 is connected to the output terminal of the fifth operational amplifier OP5 via the sixteenth resistor R16, the sixth capacitor C6 is connected to the sixteenth resistor R16 in parallel, the output terminal of the fifth operational amplifier OP5 is connected to the negative phase input terminal of the sixth operational amplifier OP6 via the seventeenth resistor R17, and the The positive input terminal of the sixth operational amplifier OP6 is grounded, the negative input terminal of the sixth operational amplifier OP6 is connected to the output terminal of the sixth operational amplifier OP6 via the eighteenth resistor R18 and the nineteenth resistor R19, the positive power supply terminal of the sixth operational amplifier OP6 is connected to the positive electrode of the first power supply VCC1, the positive electrode of the first power supply VCC1 is grounded via the seventh capacitor C7, the negative power supply terminal of the sixth operational amplifier OP6 is connected to the negative electrode of the first power supply VCC1, the negative electrode of the first power supply VCC1 is grounded via the eighth capacitor C8, wherein the second terminal of the fifteenth resistor R15 is connected to the driving voltage V d The output terminal of the sixth operational amplifier OP6 outputs a compensation voltage V comp .

[0047] In detail, Figure 5As shown, the correction module includes a twentieth resistor R20, a twenty-first resistor R21, a ninth capacitor C9, a tenth capacitor C10, and a multiplier U1. The first input terminal of the multiplier U1 is connected to the first end of the twentieth resistor R20, the second input terminal of the multiplier U1 is connected to the first end of the twenty-first resistor R21, the third input terminal of the multiplier U1 is grounded, the positive power supply terminal of the multiplier U1 is connected to the positive electrode of the third power supply VCC3, the positive power supply terminal of the multiplier U1 is also grounded after passing through the ninth capacitor C9, the negative power supply terminal of the multiplier U1 is connected to the negative electrode of the third power supply VCC3, the negative power supply terminal of the multiplier U1 is also grounded after passing through the tenth capacitor C10, the fourth input terminal of the multiplier U1 is connected to the output terminal of the multiplier U1, and the fifth input terminal of the multiplier U1 is grounded, wherein the second end of the twentieth resistor R20 is connected to the third reference voltage VREF3, the twenty-first resistor R21 is connected to the compensation voltage V comp The sixth input terminal of the multiplier U1 is connected to the sampling voltage V S .

[0048] It should be noted that the eighth resistor R8 is a platinum resistance temperature sensing element, the twelfth resistor R12 is a sliding resistor, and the nineteenth resistor R19 is a sliding resistor.

[0049] like Figures 1 to 5 As shown, the working principle of the online temperature compensation circuit provided by this application is as follows:

[0050] The reference temperature is set according to the working scenario of the port to be tested. Under the reference temperature scenario, the sampling module samples the voltage V0 of the port to be tested and obtains the sampled voltage V S , the sampling voltage V S The input correction module adjusts the resistance of the twelfth resistor R12 so that the output voltage of the fourth operational amplifier OP4 is equal to the driving voltage V d equal, so that the compensation voltage V output by the sixth operational amplifier OP6 comp Equal to zero, at the reference temperature, no compensation voltage V is required comp For the sampling voltage V S To compensate, at the reference temperature, correct the target voltage V output by the module g Equal to the voltage V0 output by the port to be tested.

[0051] When the operating temperature of the device changes, the sampling module samples the voltage V0 of the port to be tested at any temperature to obtain the sampled voltage V at the current temperature. S , due to temperature changes, the performance parameters of electronic components will change. In non-reference temperature environments, the sampling voltage V S The eighth resistor R8 in the constant current source driving unit automatically senses the temperature to change the driving voltage V d The value of the driving voltage V dInput parameter generation unit to generate compensation voltage V comp , the compensation voltage V comp and the sampling voltage V S Input correction module, perform temperature compensation, and obtain target voltage V g , target voltage V g The voltage V0 equal to the output voltage of the port to be tested at the reference temperature is used to complete the online temperature compensation of the electronic component. If the target voltage after the compensation voltage compensation has an error value, the resistance value of the nineteenth resistor R19 in the parameter generation unit is adjusted to correct the error value and improve the compensation accuracy.

[0052] The online temperature compensation circuit is calculated as follows:

[0053] The sampling module samples the voltage V0 of the port to be measured and obtains the sampled voltage V S , if the resistance of the second resistor R2 is 10 times that of the third resistor R3, and the resistance of the fifth resistor R5 is equal to the resistance of the sixth resistor R6, the expression of the sampling voltage is shown as (1):

[0054]

[0055] Among them, V S is the sampling voltage, R2 is the second resistor, R3 is the third resistor, R5 is the fifth resistor, R6 is the sixth resistor, and V0 is the port voltage to be measured.

[0056] The third operational amplifier OP3 and the NPN transistor in the constant current source driving unit form a voltage-controlled constant current to perform constant current driving. The driving voltage V d is the voltage of the eighth resistor R8 to ground, the driving voltage V d It changes linearly, the driving voltage V d The voltage is input to the negative electrode of the fifth operational amplifier OP5 through the fifteenth resistor R15.

[0057] The second reference voltage VREF2 is divided by the tenth resistor R10, the eleventh resistor R11 and the twelfth resistor R12 to obtain the voltage of the non-inverting input terminal of the fourth operational amplifier OP4. The expression of the voltage of the non-inverting input terminal of the fourth operational amplifier OP4 is shown in (2):

[0058]

[0059] Among them, V op4+ is the voltage at the non-inverting input terminal of the fourth operational amplifier OP4, V REF2 is the second reference voltage, R10 is the tenth resistor, R11 is the eleventh resistor, and R12 is the twelfth resistor.

[0060] The voltage at the non-inverting input terminal of the fourth operational amplifier OP4 is outputted by the follower of the fourth operational amplifier OP4, and then divided by the thirteenth resistor R13 and the fourteenth resistor R14, and finally inputted into the non-inverting input terminal of the fifth operational amplifier OP5. If the resistance value of the thirteenth resistor R13 is equal to the resistance value of the fourteenth resistor R14, and if the resistance value of the sixteenth resistor R16 is equal to the resistance value of the fifteenth resistor R15, the voltage at the output terminal of the fifth operational amplifier OP5 is as shown in Expression (3):

[0061]

[0062] Among them, V op5-out is the output voltage of the fifth operational amplifier OP5, V op4+ is the voltage of the non-inverting input terminal of the fourth operational amplifier OP4, R15 is the fifteenth resistor, R16 is the sixteenth resistor, V d is the driving voltage.

[0063] The output voltage of the fifth operational amplifier OP5 is output as a compensation voltage V after passing through the sixth operational amplifier OP6. comp , compensation voltage V comp As shown in expression (4):

[0064]

[0065] Among them, V comp is the compensation voltage, V op5-out is the output voltage of the fifth operational amplifier OP5, V op4+ is the voltage of the non-inverting input terminal of the fourth operational amplifier OP4, R17 is the seventeenth resistor, R18 is the eighteenth resistor, R19 is the nineteenth resistor, V d is the driving voltage.

[0066] It should be noted that the multiplier provided in this application may be AD534.

[0067] The compensation voltage V comp and the sampling voltage V S Input correction module, calculate through multiplier U1, get the target voltage V g , if the third reference voltage VREF3 is 1V, the target voltage V g The expression of is shown in (5):

[0068]

[0069] Among them, V g is the target voltage, V S is the sampling voltage, V comp is the compensation voltage, V0 is the voltage of the port to be tested, V op4+is the voltage of the non-inverting input terminal of the fourth operational amplifier OP4, R17 is the seventeenth resistor, R18 is the eighteenth resistor, R19 is the nineteenth resistor, V d is the driving voltage.

[0070] The present application also provides a control method for an online temperature compensation circuit, which is applied to the online temperature compensation circuit as described above, comprising:

[0071] Calibrate the compensation voltage at the reference temperature so that the target voltage is equal to the voltage of the port to be measured;

[0072] Sampling the voltage of the port to be tested at the current temperature to obtain a sampled voltage;

[0073] Perform temperature compensation on the sampled voltage according to the compensation voltage corresponding to the temperature difference to obtain the target voltage;

[0074] The temperature difference is the difference between the current temperature and the reference temperature.

[0075] In detail, calibrating the compensation voltage at the reference temperature so that the target voltage is equal to the voltage of the port to be measured includes: sampling the voltage of the port to be measured at the reference temperature to obtain the sampled voltage at the reference temperature; adjusting the resistance value of the resistor in the parameter compensation module so that the compensation voltage is equal to the preset voltage threshold so that the target voltage is equal to the voltage of the port to be measured. Specifically, firstly place the online temperature compensation circuit at the reference temperature, calibrate the online temperature compensation circuit, and adjust the resistance value of the twelfth resistor R12 in the parameter generation unit so that the output voltage of the fourth operational amplifier OP4 is equal to the driving voltage V d equal, so that the compensation voltage V output by the sixth operational amplifier OP6 comp Equal to zero, at the reference temperature, no compensation voltage V is required comp For the sampling voltage V S Compensation is performed to correct the target voltage V output by the module at the reference temperature. g Equal to the voltage V0 output by the port to be tested.

[0076] In detail, the sampled voltage is temperature compensated according to the compensation voltage corresponding to the temperature difference to obtain the target voltage, including: adjusting the resistance value in the compensation module based on the current temperature to obtain the compensation voltage at the current temperature; correcting the sampled voltage based on the compensation voltage at the current temperature to obtain the target voltage at the reference temperature. Specifically, when the electronic component is in the working environment, the corresponding compensation voltage V is generated according to the temperature difference between the current temperature and the reference temperature. comp , that is, the eighth resistor R8 in the constant current source driving unit automatically senses the temperature to change the driving voltage V d The value of the driving voltage V d Input parameter generation unit to generate compensation voltage Vcomp , the compensation voltage V comp and the sampling voltage V S Input correction module, perform temperature compensation, and obtain target voltage V g , so that the target voltage V at any temperature g Equal to the voltage V0 output by the port under test at the reference temperature.

[0077] The present application also provides a temperature compensation instrument, which includes the online temperature compensation circuit as described above, and is used to perform temperature compensation on the voltage of the port to be measured to improve the accuracy of the port output data.

[0078] The present application provides an online temperature compensation circuit and a control method thereof, and a temperature compensation instrument. The circuit includes a sampling module, a parameter compensation module, and a correction module. The sampling module samples the voltage of the port to be measured to obtain a sampled voltage. The parameter compensation module generates a compensation voltage according to the reference voltage and the temperature change before the current temperature. The correction module corrects the sampled voltage based on the compensation voltage to obtain a target voltage, so that the target voltage is equal to the voltage of the port to be measured at the reference temperature at any temperature. The online temperature compensation circuit provided by the present application realizes the temperature measurement of the circuit by adjusting the resistance value of the resistor. The temperature measurement range is wide, and the online temperature compensation of the circuit is realized. The temperature adjustment range is wide and the precision is high. After the device leaves the factory, the sensitivity of the related instrument decreases. The customer can adjust it by himself without returning to the factory for repair, which improves the operability of the customer.

[0079] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. An online temperature compensation circuit, characterized in that: include: A sampling module is used to sample the voltage of the port to be measured to obtain a sampled voltage; A parameter compensation module, used for generating a compensation voltage according to a change between a current temperature and a reference temperature; A correction module is connected to the sampling module and the parameter compensation module, and corrects the sampling voltage according to the compensation voltage to obtain a target voltage, wherein the target voltage is equal to the voltage of the port to be measured at the reference temperature.

2. The online temperature compensation circuit according to claim 1, characterized in that: The sampling module includes a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a first capacitor, a second capacitor, a first operational amplifier and a second operational amplifier. The positive phase input terminal of the first operational amplifier is grounded after passing through the first resistor, the first terminal of the second resistor is connected to the negative phase input terminal of the first operational amplifier, the negative phase input terminal of the first operational amplifier is connected to the output terminal of the first operational amplifier after passing through the third resistor, the positive power supply terminal of the first operational amplifier is connected to the positive electrode of the first power supply, the positive electrode of the first power supply is also grounded after passing through the first capacitor, the negative power supply terminal of the first operational amplifier is connected to the negative electrode of the first power supply, the negative electrode of the first power supply is also grounded after passing through the second capacitor, the output terminal of the first operational amplifier is connected to the negative phase input terminal of the second operational amplifier after passing through the fifth resistor, the positive phase input terminal of the second operational amplifier is grounded after passing through the fourth resistor, the negative phase input terminal of the second operational amplifier is connected to the output terminal of the second operational amplifier after passing through the sixth resistor, wherein the second terminal of the second resistor is connected to the voltage of the port to be measured, and the output terminal of the second operational amplifier outputs the sampling voltage to the outside.

3. The online temperature compensation circuit according to claim 2, characterized in that: The parameter compensation module includes a constant current source driving unit and a parameter generating unit. The constant current source driving unit generates a driving voltage based on a second power supply under the drive of a first reference voltage. The parameter generating unit is connected to the constant current source driving unit. The parameter generating unit generates a compensation voltage according to the second reference voltage and the driving voltage.

4. The online temperature compensation circuit according to claim 3, characterized in that: The constant current source driving unit includes a third capacitor, a fourth capacitor, a seventh resistor, an eighth resistor, a ninth resistor, an NPN transistor and a third operational amplifier, wherein the positive phase input terminal of the third operational amplifier is grounded after passing through the third capacitor, the positive power supply terminal of the third operational amplifier is connected to the positive electrode of the first power supply, the negative power supply terminal of the third operational amplifier is connected to the negative electrode of the first power supply, the negative phase input terminal of the third operational amplifier is connected to the output terminal of the third operational amplifier after passing through the fourth capacitor, the output terminal of the third operational amplifier is also connected to the base of the NPN transistor after passing through the seventh resistor, the collector of the NPN transistor is connected to the second power supply, the emitter of the NPN transistor is grounded after passing through the eighth resistor and the ninth resistor, the negative phase input terminal of the third operational amplifier is also connected to the common end of the eighth resistor and the ninth resistor, wherein the positive phase input terminal of the third operational amplifier is connected to the first reference voltage, and the emitter of the NPN transistor outputs the driving voltage to the outside.

5. The online temperature compensation circuit according to claim 3, characterized in that: The parameter generating unit includes a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor, a fourth operational amplifier, a fifth operational amplifier, and a sixth operational amplifier; The second reference voltage is connected to the non-inverting input terminal of the fourth operational amplifier after passing through the tenth resistor, the non-inverting input terminal of the fourth operational amplifier is also grounded after passing through the eleventh resistor and the twelfth resistor, the positive power supply terminal of the fourth operational amplifier is connected to the positive electrode of the first power supply, the positive power supply terminal of the fourth operational amplifier is grounded after passing through the fifth capacitor, the negative power supply terminal of the fourth operational amplifier is connected to the negative electrode of the first power supply, the negative input terminal of the fourth operational amplifier is connected to the output terminal of the fourth operational amplifier, the output terminal of the fourth operational amplifier is connected to the first end of the fourteenth resistor after passing through the thirteenth resistor, the first end of the fourteenth resistor is also connected to the non-inverting input terminal of the fifth operational amplifier, the second end of the fourteenth resistor is grounded, the first end of the fifteenth resistor is connected to the a negative phase input terminal of a fifth operational amplifier, the negative phase input terminal of the fifth operational amplifier is connected to the output terminal of the fifth operational amplifier via the sixteenth resistor, the sixth capacitor is connected in parallel with the sixteenth resistor, the output terminal of the fifth operational amplifier is connected to the negative phase input terminal of the sixth operational amplifier via the seventeenth resistor, the positive phase input terminal of the sixth operational amplifier is grounded, the negative phase input terminal of the sixth operational amplifier is connected to the output terminal of the sixth operational amplifier via the eighteenth resistor and the nineteenth resistor, the positive power supply terminal of the sixth operational amplifier is connected to the positive electrode of the first power supply, the positive electrode of the first power supply is grounded via the seventh capacitor, the negative power supply terminal of the sixth operational amplifier is connected to the negative electrode of the first power supply, the negative electrode of the first power supply is grounded via the eighth capacitor, The second end of the fifteenth resistor is connected to the driving voltage, and the output end of the sixth operational amplifier outputs the compensation voltage to the outside.

6. The online temperature compensation circuit according to claim 3, characterized in that: The correction module includes a twentieth resistor, a twenty-first resistor, a ninth capacitor, a tenth capacitor, and a multiplier, wherein the first input terminal of the multiplier is connected to the first end of the twentieth resistor, the second input terminal of the multiplier is connected to the first end of the twenty-first resistor, the third input terminal of the multiplier is grounded, the positive power supply terminal of the multiplier is connected to the positive electrode of the third power supply, the positive power supply terminal of the multiplier is further grounded after passing through the ninth capacitor, the negative power supply terminal of the multiplier is connected to the negative electrode of the third power supply, the negative power supply terminal of the multiplier is further grounded after passing through the tenth capacitor, the fourth input terminal of the multiplier is connected to the output terminal of the multiplier, and the fifth input terminal of the multiplier is grounded, wherein the second end of the twentieth resistor is connected to the third reference voltage, the twenty-first resistor is connected to the compensation voltage, and the sixth input terminal of the multiplier is connected to the sampling voltage.

7. A control method for an online temperature compensation circuit, characterized in that: An online temperature compensation circuit as claimed in any one of claims 1 to 6, comprising: Calibrate the compensation voltage at the reference temperature so that the target voltage is equal to the voltage of the port to be measured; Sampling the voltage of the port to be tested at the current temperature to obtain the sampled voltage; Performing temperature compensation on the sampled voltage according to a compensation voltage corresponding to the temperature difference to obtain the target voltage; The temperature difference is the difference between the current temperature and the reference temperature.

8. The control method of the online temperature compensation circuit according to claim 7, characterized in that: Calibrating the compensation voltage at the reference temperature so that the target voltage is equal to the voltage of the port to be measured includes: Sampling the voltage of the port to be measured at the reference temperature to obtain a sampled voltage at the reference temperature; The resistance value of the resistor in the parameter compensation module is adjusted so that the compensation voltage is equal to a preset voltage threshold, so that the target voltage is equal to the voltage of the port to be measured.

9. The control method of the online temperature compensation circuit according to claim 7, characterized in that: Performing temperature compensation on the sampled voltage according to a compensation voltage corresponding to the temperature difference to obtain the target voltage includes: Adjust the resistance value of the resistor in the parameter compensation module based on the current temperature to obtain a compensation voltage at the current temperature; The sampled voltage is corrected based on the compensation voltage at the current temperature to obtain the target voltage at the reference temperature.

10. A temperature compensation instrument, characterized in that: It comprises the online temperature compensation circuit as described in any one of claims 1 to 6, and is used for performing temperature compensation on the voltage of the port to be measured.

Images